1. Technical Field
This invention is directed toward a system and method for improving digital images. More specifically, the invention is directed towards a photo illumination technology that facilitates user-selectable illumination of an existing photo ranging from full artificial flash illumination to ambient light illumination and every gradation between.
2. Background Art
Recently, some efforts have been made to do things with digital photography that are difficult or impossible with analog photography. Many digital cameras now come with a capacity to shoot short video clips. Some digital camera software comes equipped with image-stitching capabilities that allow one to create larger panoramas sewn together from smaller, overlapping images of the same scene. However, none of these digital photography techniques can be used to vary the amount of flash after the picture is taken to obtain the optimum illumination level for the subject matter to be photographed.
A flash typically allows the photographer to control the lighting situation when the picture is taken. If insufficient natural light is available, a flash may be used to increase the overall illumination. Sometimes the subject matter to be photographed is too dimly illuminated to make a photograph without supplementary lighting. Additionally, flash may be used in order to change or improve the natural lighting. This is known as fill flash. For instance, pictures taken of people outside on a bright day often show the subjects squinting due to the glare caused by the sun. A good solution to this problem is to move the subjects into the shade and to use flash to fill in the shadows.
Either with a digital or with an analog camera, obtaining the correct amount of flash is difficult. Often images photographed are overexposed—too much light reached the film when the picture was taken. There are many reasons that this occurs. The flash could have been too bright or the flash setting was in some other way improper. The shutter speed could have been too slow or the aperture could have been too large. Alternately, the images could be underexposed—that is, not enough light reached the film, and the picture comes out dark and indistinguishable. In this case, film speed, shutter speed, aperture and flash settings can all have an effect. With so many variables it is difficult for even the most experienced photographer to obtain a photograph with the proper amount of flash.